1. Technical Field
The present invention relates to an electric optical apparatus, a driving method thereof and an electronic device.
2. Related Art
An electrophoretic display apparatus that includes a control transistor, a maintenance capacitance and a driving transistor within a pixel is known in the related art (for example, JP-A-2008-176330). In the pixel of the electrophoretic display apparatus described in JP-A-2008-176330, the maintenance capacitance is charged by an image signal that is input through the control transistor and the driving transistor flows a current to a pixel electrode according to a voltage of the maintenance capacitance. Thus, brightness display can be obtained according to an amount of charge (current×time) that is supplied to the pixel electrode.
In the pixel described in JP-A-2008-176330, the current Is that flows in the driving transistor is presented by the Equation shown below. Here, W is a channel width, L is a channel length, Cox is a constant that is present in an equation ∈ox/tox (∈ox: a dielectric constant of gate oxide film, tox: a thickness of a gate insulating film), μ is mobility, Vth is a threshold value voltage, and Vg and Vs are a gate voltage and a source voltage respectively.
      I    s    =            1      2        ⁢          W      L        ⁢          C      ox        ⁢                  μ        ⁡                  (                                    V              g                        -                          V              s                        -                          V              th                                )                    2      
Here, Vth of the above-described Equation has a variation in regard to each of the transistors which is caused by a variation of a position of film formation during a transistor manufacturing process. Thus, the current Is is varied in each of the pixels and display tones are different to each other so that unevenness display occurs.